The Influence of the Velocit Dispersion on the Velocity–Density Relation in the Disk Model of the Galaxy
Autor
Sikora, Szymon
Bratek, Łukasz
Jałocha, Joanna
Kutschera, Marek
Opublikowane w
Acta Physica Polonica B
Numeracja
Vol. 48, No. 11
Strony
2071-2092
Data wydania
2017
Miejsce wydania
Kraków
Wydawca
Faculty of Physics, Astronomy and Applied Computer Science. Jagiellonian University
Język
angielski
ISSN
1509-5770
DOI
10.5506/APhysPolB.48.2071
Abstrakt
Taking the velocity dispersion term into account in the Jeans equation describing the disk model, counterintuitively allows to reduce the local mass-to-light ratio at the outskirts of flattened galaxies, and stop the unbound growth of mass function. This is possible thanks to a more intertwined relation between the gravitational potential and the rotation curve than for spheroidal systems. This effect is illustrated on the example of galaxy UGC 6446 by finding iteratively the column mass density from the rotation curve supplemented with an isotropic velocity dispersion profile in the disk plane. Along with galactic magnetic fields, this effect would allow to reduce the local mass-to-light ratio at the galactic outskirts.
